Gas sealed explosive propelling arrangement



Jan. 28, 1964 1. R. BARR 3,119,302

GAS SEALED EXPLOSIVE PROPELLING ARRANGEMENT Filed June 5. 1961 4o /Rw//v R. BARR INVENTOR.

BY DONALD M. SANDLER 20 F G 5 THOMAS J HOLDEN ATTORNEYS United States Patent 3,119,302 GAS SEALED EXPLQSHVL lRUPELLlNG ARRANQlEh BENT Erwin l2. Barr, Luthervilie, Md, assignor to Aircraft Armaments, inc, Coclreysville, With, a corporation of Maryland Filed June 5, 1% Ser. No. 114,891 6 Claims. (Cl. i 1) This invention relates to gas sealed propelling arrangements, the invention being illustrated as embodied in a separable bolt having an explosive charge which, when selectively actuated, causes the bolt to separate whereby adjacent bulkheads to which the bolt may be connected can be separated.

in explosively actuated separable bolts, as well as other propelling arrangements for various materials to be pro pelled it is often desirable to seal the generated propelling gases from the surrounding atmosphere, as well as from the material being propelled. It is also often of importance to provide a high initial propelling impulse force on the propelled material.

It is accordingly a feature of the present invention to provide an improved gas sealed propelling arrangement in which a high initial impulse force is exerted on the material being propelled.

In tse illustrative embodiment this feature is achieved through the embodiment of an explosive charge actuated gas propelling device, which in the present instance is a separable bolt, and which incorporates a propellablecharge-carrying cup-shaped gas seal having a closed tube end extending toward and adjacent the explosive charge, with gas flow inhibiting or sealing means at this closed tube end of the seal to inhibit or substantially seal off forward gas flow from the explosive charge Zone at this closed end to the zone laterally surrounding this chargecarrying tubular portion of the seal during at least the initial portion of longitudinal movement of the tubular portion of the seal, and thereby yielding among its advantages the efiecting of a higher initial propelling pressure and propelling force on the closed tube end of the cup seal and the charge of material which is initially carried by and within the tubular portion of the seal than would be present without this gas flow inhibiting or sealing means.

Still other objects and attendant advantages will become apparent to one skilled in the art from a reading of the following detailed description of one preferred physi cal embodiment constructed in accordance therewith, taken in conjunction with the accompanying drawings where- FIGURE 1 shows separablebolts connecting a twostage rocket, with parts cutaway to illustrate internal construction.

FKGU'RE 2 is a sectional View of a separable bolt taken generally along the line 2-2, and showing how the bolt mechanically interconnects adjacent bulkheads.

FIGURE 3 is a sectional view similar to FIGURE 2, but showing how actuation of the bolt causes the mechanical connection between the bulkheads to fail.

FIGURE 4 is a sectional view similar to- FIGURE 3, but showing how propellant gases react to thrust the bull heads apart.

FIGURE 5 shows how all of the propellent gases pro- W aliases Fa'tented Jan. 28, 1964 ice duced when the bolt is actuated are entirely contained within a closed chamber.

Referring now to FIGURE 1, the interconnection between adjacent stages it? and ill of rocket 12. is shown. doth stages are cylindrical and have abutting ends 13. Bulkhead in on stage ll) is spaced from bulkhead 15 on stage Ill. A plurality of separable bolts 16 interconnect bulkhead l t to bulkhead 15 such that stages Ill and 11 form an integral structural unit.

Referring now to FIGURE 2, bolt 16 is seen to include tubular sleeve 17 extending between bulkheads l4 and 15. Boss 13 adjacent one end of sleeve 17 abuts bulkhead which has aperture 19 through which the sleeve extends. This end of sleeve 17 is threaded to receive locking unt 2% which securely connects the sleeve to bulkhead 1d. The opposite axial end of sleeve 17 is closed and or" reduced diameter to form threaded bolt 21 which extends through aperture 22 in bulkhead 15. Lock nut 23 threaded onto bolt 21 securely connects the sleeve to bulkhead 15. in the above manner, the axial ends are rigidly connected to opposite bulkheads.

Sleeve 17 has cylindrical bore 24 with threaded opening 25 at the end of the sleeve connected to bulkhead 14. Closure body 26 is threaded into opening 25 for closing the same, and has an exposed end 27 threaded to receive an electrical connector 23. Stepped recess 29 in closure 26 is provided for electrical primer 3% used to detonate a charge contained in pocket 31 when power is supplied through connection 23 to pins 32 interconnected by bridge wires 33.

Cylindrical push rod 34 is smaller in diameter than the bore. Projection 35 concentric with red 34 on one end thereof is engaged in recess 36 in the closed end of sleeve 17 adjacent bulkhead 15 to limit movement of the rod toward bulkhead 15. As seen in the drawing, rod 34 is concentric in bore 24 and extends toward closure 2'6, terminating in a transverse face 37. Any other equivalent connection between rod 34 and bulkhead 15 could be used.

To disconnect bulkheads lid and 15, weakened portion is provided in sleeve 17 in the form of a circumferential groove. The sleeve thickness is thus locally reduced resulting in failure at the groove when a predetermined force is applied to the bulkheads tending to separate them. Such force is generated by propellent gases acting on casing 39.

Casing 33 is located in bore 2e adjacent the closed end thereof and is interposed between sleeve 1'7 and rod 34. Casing 39 includes a first tubular section 443 of substantially the same diameter as the bore engaged therein. One end of section so is rigidly attached to closure as by suitable mean-s. As previously described, closure 26 is rigidly attached to sleeve 17. Section i-tl thus extends away from closure as and constitutes a portion of the casing that is fixed to the sleeve. Casing 39 also includes a circumferential flange 4-1, at the end of section ill remote from closure 26, that extends into the bore at a point axially spaced from the closure. Cylindrical deformable tube 42 having one end connected to flange 41 is a portion of the casing that is concentric with both section id and bore 2d, and extends toward closure 26 to define annular chamber 5%. Tube &2 is engaged with rod 34 for coaxially supporting the same in the bore. The other end of tube 42 has transverse face 46 engaged with face 37 on rod 34.

Face 43 forms a casing closure closing that end of the tube. Thus, the tube forms a portion of the closed annular chamber 50.

Face 43 of the casing is slightly spaced from primer 3b attached to the closure body. However, annular extension 51 on closure 26 extends into annular chamber as best seen in FIGURE 2. Thus, extension 51 effective- 1y separates annular chamber 59 from primary chamber 52 defined in part by the space between face 43 and the closure body. Actually, both primary chamber 52 and annular chamber are small.

In operation, poover supplied to pins 32 causes bridge wires 33 to ignite a charge in pocket 3-1. Because primary chamber 52 is relatively small, tie pressure therein reaches a relatively high level exerting on face 3 an axial force directed toward bulkhead i5. Annular extension 51 on the closure body prevents a significant amount of gas from expanding into chamber 50 with the result that a very large axial force is exerted on rod 34 imparting axial movement thereto away from bulkhead 14 since the shoulder connecting rod 34 to extension 35 prevents relalive movement of rod 34 toward bulkhead As a re- 'sult, sleeve 17 fails at groove 3% after initial axial displacement of face 4-3, tube 42 sliding relative to extension 51.

As shown in FIGURE 3, propellant gases in the primary cha'mbe' expand into annular chamber 53 as face 43 is axially displaced beyond the free edge of annular extension 51. Such axial displacement of face 43 along the bore away from the closure deforms tube 42 into another tube substantially the same diameter as the bore that extends from the portion of casing 39 fixed to the sleeve away from the closure. Tube 42, however, remains connected to tube ill throughout axial displacernent of face 43 for entirely containing the propellant gases within a closed chamber. In this way, the energy in the gases is not dissipated as in the normal case, but is used to thrust the rod away from bulkhead 14.

Rod 34 is coaxially supported during axial displacement of face 43 by the portion of tube 42 that remains undeforrned prior to maximum axial displacement of the face as can be seen in FIGURE 3. As a result of this construction, the propellant gases react first in a small volume to achieve high pressures and cause a high resultant axial force to be applied to the push rod. This causes failure of the mechanical connection between the bulkheads. Next, the deformable tube coaxially supports the push rod as deformation occurs. All the propellant gases remain confined so that all Olf the energy in the gases is used to provide a thrust separating the bulkheads.

While the invention has been illustrated with respect to a single physical embodiment constructed in accordance therewith, it will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the scope and spirit of the invention. For instance, other desired charges than a solid rod can be propelled according to this invention, if so desired, and the invention can be practiced in other arrangements than separable bolts. Also, while an electric primer is shown in the illustrative embodiment, a mechanical primer could be used instead. Further propellant gases could be supplied from a gas generator :source removed from the connector and acting on the closed end of the tube seal. Accordingly, it is to be understood that the invention is not to be limited by the specific illustrative embodiment, but only by the scope of the appended claims.

What is claimed is:

1. A gas sealed propelling arrangement comprising a casing having a bore formed therein; a cup-shaped diaphragm seal having a longitudinally extending tubular body port-ion closed at one end and extending lengthwise along a portion of the length of said bore, a transversely out-folded end portion integral with and formed at the opposite end of said tubular body portion, and means connecting said outfolded end portion to said casing in substantially gas pressure sealing relation; explosive charge gas pressure generating means adjacent said one closed end of said cup-shaped diaphragm seal, an annular pressure seal unit mounted at said one closed end of and in contact with said diaphragm seal extending transversely beyond the end face of said closed end to substantially seal said explosive charge gas pressure generating means from the zone radially external of the circumferentially outer wall of said tubular body portion, whereby upon actuation of said explosive charge gas pressure generating means the explosive gas pressure action on said tubular portion of said diaphragm is substantially restricted to endwise thrust on said closed end of said tubular portion during at least the initial portion of endwise longitudinal movement of said diaphragm, and a longitudinally propcllable charge of material disposed within and carried by said tubular portion of said diaphragm.

2. Apparatus according to claim 1 wherein said propellable charge is a rig-id body.

3. Apparatus according to claim 1 wherein said casing encloses said diaphragm and said propellable charge, said casing bore being shorter than the combined effective length of said propellable charge within said bore and the longitudinally out-folded effective length of said dia phragm.

4-. Apparatus according to claim 1 wherein said annular pressure seal member is a sleeve surrounding said tubular portion of said diaphragm at said closed end thereof.

5. A gas sealed propelling arrangement comprising a casing having a bore formed therein; a cup-shaped diaphragm seal having a longitudinally extending tubular body portion closed at one end and extending lengthwise along a portion of the length of said bore, a transversely out-folded end portion integral with and formed at the opposite end of said tubular body portion, and means connecting said outfolded end portion to said casing in substantially gas pressure sealing relation explosive charge gas generating means adjacent said one closed end of said cup-shaped diaphragm seal, and external of said tubular body portion, and an annular sleeve separable from said seal and surrounding said tubular portion of said diaphragm at said one closed end thereof and thereby inhibiting gas flow from the zone adjacent said explosive charge gas generating means and one closed end toward said outfolded opposite end portion of said seal to thereby effect an initial higher gas pressure within the zone adjacent said closed end than would otherwise be present without said annular sleeve, and a longitudinally propellable charge of material disposed Within and carried by said tubular portion of said diaphragm.

6. A gas sealed propelling arrangement comprising a casing having a bore formed therein; a cup-shaped diaphragm seal having a longitudinally extending tubular body portion closed at one end and extending lengthwise along a portion of the length of said bore, a transversely out-folded end portion integral with and formed at the opposite end of said tubular body portion, and means connecting said outfolded end portion of said casing in substantially gas pressure sealing relation; explosive charge gas pressure generating means adjacent said one closed end of said cup-shaped diaphragm seal, said bore having a first annular confining wall portion disposed about said one closed end of said tubular portion and being substantially complementary to and surrounding the corresponding adjacent circumferential periphery of said tubular portion of said diaphragm, said bore having a second annular confining wall portion disposed contiguous with and extending longitudinally beyond said transversely out-folded opposite end portion of said diaphragm and being of larger diameter than said first wall portion by an amount in excess of the circumferential thickness of said tubular portion of said diaphragm, whereby said first wall portion serves as a gas flow restricting means and a lateral guide for movement of said tubrular portion during at least the initial lengthwise movement of said tndinally propellable charge of material disposed within and carried by said tubular portion of said diaphragm.

tubular portion away from said gas pressure generating References Cited in the file of this Patent means, and the relatively larger circumferential size of Said second Wall portion permitting sequential incremental 5 UNITED STATES PATENTS cold flow rolling out-folding of said tubular portion of 1,077,472, Hoffmann Nov. 4, 1913 said diaphragm to a new inside-out shape bounded by 2,421,807 Richey et a1. Tune 10, 1947 said larger diameter Wall portion during longitudinal 2,575,051 Rockwell Nov. 13, 1951 movement of said diaphragm therethrough, and a longi- 2,830,539 Cecil Apr. 15, 1958 10 2,883,910 Nessler Apr. 28, 1959 

1. A GAS SEALED PROPELLING ARRANGEMENT COMPRISING A CASING HAVING A BORE FORMED THEREIN; A CUP-SHAPED DIAPHRAGM SEAL HAVING A LONGITUDINALLY EXTENDING TUBULAR BODY PORTION CLOSED AT ONE END AND EXTENDING LENGTHWISE ALONG A PROTION OF THE LENGTH OF SAID BORE, A TRANSVERSELY OPPOSITE END OF SAID TUBULAR BODY PORTION, AND MEANS CONNECTING SAID OUTFOLDED END PORTION TO SAID CASING IN SUBSTNTIALLY GAS PRESSURE SEALING RELATION; EXPLOSIVE CHARGE GAS PRESSURE GENERATING MEANS ADJACENT SAID ONE CLOSED END OF SAID CUP-SHAPED DIAPHRAGM SEAL, AN ANNULAR PRESSURE SEAL UNIT MOUNTED AT SAID ONE CLOSED END OF AND IN CONTACT WITH SAID DIAPHRAGM SEAL EXTENDING TRANSVERSELY BEYOND THE END FACE OF SAID CLOSED END TO SUBSTANTIALLY SEAL SAID EXPLOSIVE CHARGE GAS PRESSURE GENERATING MEANS FROM THE ZONE RADIALLY EXTERNAL OF THE CIRCUMFERENTIALLY OUTER WALL OF SAID TUBULAR BODY PORTION, WHEREBY UPON ACTUATION OF SAID EXPLOSIVE CHARGE GAS PRESSURE GENERATING MEANS THE EXPLOSIVE GAS PRESSURE ACTION ON SAID TUBULAR PORTION OF SAID DIAPHRAGM IS SUBSTANTIALLY RESTRICTED TO ENDWISE THRUST ON SAID CLOSED END OF SAID TUBULAR PORTION DURING AT LEAST THE INITIAL PORTION OF ENDWISE LONGITUDINAL MOVEMENT OF SAID DIAPHRAGM, AND A LONGITUDINALLY PROPELLABLE CHARGE OF MATERIAL DISPOSED WITHIN AND CARRIED BY SAID TUBULAR PORTION OF SAID DIAPHRAGM. 